Robots and Anthropomorphism
Margaret A. Boden
University of Sussex
Abstract
Our natural tendency to anthropomorphism, grounded in
Theory of Mind and related psychological mechanisms, is
crucial to our interactions with robots. Some relatively superficial aspects of robots (e.g. physical appearance) can
trigger animistic, even empathetic, responses on the part of
human beings. Other factors are more subtle, e.g. various
aspects of the language (if any) used by the artifice, and/or
of the thinking-processes apparently going on. Robotics
(like AI in general) promises/threatens to alter how people
think about themselves. Unlike AI programs, robots are
physical entities moving around in a physical world. This
makes them more humanlike in various ways. But physicality isn't the same thing as embodiment. For someone who
wants to insist on a distinction between robots and humans,
the fact that robots aren't living things is likely to be important.
Introduction
Nearly a quarter-century ago, the social psychologist Neil
Frude (1983) predicted that humanlike robot "companions"
would attract deep responses, even including emotional
attachments, because of the universal human tendency to
animism. (He said much the same about 'human' figures in
the type of audiovisual display which is now called virtual
reality; however, I'll ignore screen-based VR systems
here.)
By animism, he meant ascribing psychological predicates
to things that don't literally merit them. Strictly, these
things include both living organisms and non-living things.
Certain animistic religions, for instance, feature trees,
snakes, winds, or rivers as having intentions (and knowledge) of simple kinds. But Frude was especially interested
in cases where the predicates involved cover all or most of
the mental characteristics we ascribe to human beings, and
where the target of the animism actually looks and/or behaves in some ways like a human being. In short, he was
thinking of the strong form of animism known as anthropomorphism, and of specifically 'humanlike' targets such as
dogs, dolls, and teddy bears--and, crucially, robots.
A walking, talking, cuddly robot--perhaps even one
bearing a physical resemblance to one's favourite film star,
and speaking in something like his/her voice--would (he
said) inevitably, irresistibly, attract our interest and empathy. If it could detect emotions in its human owner/partner,
either verbally and/or by means of facial expressions, or
express 'emotions' in one or both of those ways on its own
behalf, the effect would be even more compelling.
By "compelling", here, Frude meant psychologically, not
philosophically, compelling. I'll follow him in ignoring the
philosophical question of whether a robot could 'really'
have psychological properties. I'll assume (as explained in
Section II) that the robots of the foreseeable future will be
psychologically crude in comparison to their human users:
no Proustian subtleties, there. But I shan't ask whether, in
principle, any conceivable robot could really experience
emotions (even relatively simple ones), or really understand language (even of a primitive kind).
Rather, my questions here are (i) whether people inte racting with humanoid robots would, in fact, spontaneously
respond to them as if that were the case, and (ii) whether
their ideas about themselves and other human beings would
be altered as a result. Those questions are answered in
Sections III and IV, respectively. First, we must ask
whether there's any chance of Frude's imagined robots ever
seeing the light of day.
II: Future, fiction, or fantasy?
When Frude wrote his book, it was science fiction. To be
sure, he himself thought of it as prediction, not fiction. But
he vastly underestimated the theoretical and technological
difficulties involved in bringing his predictions to pass.
Admittedly, AI/robotics--nearly a quarter-century later-has made a start in all the relevant dimensions, including
some he didn't even mention (Boden 2006: 13.vi.d). These
include--among other things--NLP, speech-processing
(wherein computer-voices can be given appropriate local
accents: Fitt and Isard 1999), visual recognition of facial
expressions, modelling of emotion (e.g. different types of
anxiety, depending on the urgency, importance, and priority-orderings of the goals involved: Wright, Sloman, and
Beaudoin 1996), and the use of flexible skin like materials
on the robot's 'face'--with an underlying 'musculature' capable of mimicking human expressions. In principle, although this too is science fiction at present, a competent
visual face-recognizer might even detect when the human
was lying (Ekman 2001). In other words, Frude's futuristic
vision wasn't pure fantasy.
But that's not to say that the highly humanoid robots he
envisaged are just around the corner. In my opinion, indeed, they never will be. The difficulty of achieving human-level NLP, for example, is just too great.
Frude imagined AI-companions that could converse se nsibly with their human owners (surely not 'partners'?) about
a huge range of topics, just as your colleagues and nextdoor neighbours can. NLP systems are already being used
by some large corporations to stand in for humans as 'customer care' agents. But they exploit a limited menu of
stock-phrases concerning a limited set of topics. Fully
'Frude-ian' programs would be quite another matter.
Certainly, we could forgive an AI system for not being to
talk about quantum mechanics, or even football: after all,
you, or your neighbour, may not be able to do that either.
But the conversational limitations of individual human beings can't be used in Frude's defence here (as human mistakes can be used to counter anti-AI arguments based on
Godel's theorem). For even someone knowing next to
nothing about these specialist domains could make some
attempt at conversation about them, if only to crack a joke
in order to change the subject.
Changing the subject, of course, requires both discussants
to track the focus of attention. This involves, among other
things, interpreting anaphora correctly: every occurrence of
"it", for example. This is a subtle matter, which people
achieve mostly unawares. NLP research indicates, in my
judgment, that an AI system that can keep track of the constantly shifting focus of everyday conversations isn't feasible in the general case (Grosz 1977; Grosz and Sidner
1979; McKeown 1985.) Part of the problem, here, is that
indefinitely various world-knowledge would be needed to
cope with every occurrence of "it" (physics and football,
again).
In short, a robot that could talk to you intelligently, never
mind humorously, about virtually anything simply isn't on
the cards. (And a good thing too: shivers run up my spine
when I consider Frude's vision of generations of lonely old
people, deserted by friends and children, interacting only
with their domesticated robots.)
It doesn't follow, however, that a robot of the future
couldn't talk to you, if only in a fairly stilted fashion, about
a few choice topics--football included. It might even be
able to come up with many different conversations about a
given topic on successive days, as a human companion
could. That would probably require it to be locked into the
Internet, with the ability to find and interpret the latest
news about (for instance) football matches, hirings and
firings, and--ideally--the associated celebrity gossip: a
companion unable to remark on David Beckham's looks
and lifestyle, as well as his career on the pitch, would be
disappointing for many people. But even if that's not feasible, an AI system might be able to converse about his professional activities, and follow the discussions on the sports
pages of the newspapers. And we've seen that 'human'
voices, and humanoid 'faces', are already on the horizon.
So Frude's prediction stands: robot companions, disappointing though they might be in comparison with human
acquaintances, are possible--and if not inevitable, perhaps
probable. According to Frude, these less-than-human artefacts would be persuasive enough to excite anthropomorphic responses on your/our part. Was he right?
III: Animism in action
If Frude was wrong about the degree of technological difficulty, he was right about the animism--wherein something
non-human (be it a god, a dog, a teddy-bear, or a robot) is
'naturally' regarded, to some degree, as though it were human. Animism is, as he said, a deep impulse in human beings. And its strong version, anthropomorphism, would
indeed be excited by humanoid robots of the type sketched
above.
In discussing that prediction today, we don't have to rely
merely on our general knowledge and common sense, as
Frude did. The last twenty-five years of research in developmental psychology strongly suggest that anthropomorphism, like weaker forms of animism, is rooted in a nearuniversal computational mechanism in human minds.
("Near-universal", because a minority of individuals,
namely people with autism, appear not to possess it: Frith
1989/2003; Baron-Cohen 1995.) Specifically, it is rooted in
what psychologists call Theory of Mind (ToM).
To possess ToM is to be able to see other people as
agents, each with their own view of the world. Infants can't
do this. (That's why they don't lie: they can't imagine that
someone else could be deceived into believing something
which they know to be false.) Gradually, however, they
develop the ability to ascribe diverse beliefs (including
false beliefs) and intentions to other people, and to use
these in predicting and interpreting others' behaviour. (For
the first experiments on this, see Wimmer and Perner 1983;
since then, ToM has become something of an experimental
industry.)
The computational mechanisms underlying ToM are still
unclear. For instance, there's an ongoing controversy about
whether the child actually develops a theory enabling it to
generate hypotheses--i.e. animistic interpretations--and
conclusions (as the label "ToM" suggests), or whether it
develops the ability to simulate (empathize with) the mental states of other people (Davies and Stone 1995a,b).
There's also debate about whether this distinction holds up,
if carefully considered (Heal 1994). At a more detailed
level, it's unclear whether, as some researchers have
claimed, ToM involves a combination of general information-processing mechanisms with a dedicated four-slot
ToM representation (Leslie 2000). There's dispute also
about whether--or, better, to what extent--other species,
such as chimps, possess ToM (Tomasello et al. 2003a,b).
However, one doesn't have to know just how a psych ological phenomenon works in order to see (some of) its
effects. And it's significant, here, that ToM has recently
been posited as a root of animism in religion (Boyer 1994).
Anthropologists have long reported a host of examples of
animism, in both weak and strong (i.e. anthropomorphic)
forms. By definition, animism relies on familiar, folkpsychological, concepts--which are grounded in ToM. But
anthropologists and theologians alike point out that religious concepts are typically anomalous in some way (a fact
which the religious believers themselves admit, and even
celebrate). For example, one aspect of ToM is the realiza-
tion that people in different places will perceive--attain
knowledge of--different things (Wimmer and Perner 1983).
But God, in the monotheistic religions, sees/knows everything. And in animist religions, a tree, snake, or river may
have (limited) beliefs and wishes--which in non-religious
contexts they cannot. This conceptual anomalousness, Pascal Boyer (1994) has argued, is largely why religions are
both fascinating and slippery/unfalsifiable.
What's relevant for our purposes is that Frude's commonsense hunch about the near-unavoidability of animism can
now be backed up by scientific evidence from anthropology as well as psychology.
Further evidence has come from neuroscience. To d
evelop ToM depends, in part, on first developing a tendency
to pay attention to other human individuals (which autistics
typically don't do). Psychologists have shown that babies
very soon lock onto their carer's eyes, and soon come to
follow their gaze. Since Frude wrote his book, neuroscientists have discovered that there appears to be a universal
basis for the development not only of face-recognition, but
also of spontaneous engagement with (attention to) the
eyes of a face (Johnson and Morton 1991). (The two cerebral mechanisms responsible for face-recognition, which
develop at different times, have been experimentally studied in chicks but appear to be present in human babies
also.) This mutual locking of gaze, in turn, scaffolds a huge
range of carer-infant interactions, including turntaking in
language (Hendriks-Jansen 1996).
The varied scientific research on ToM suggests that--as
Frude predicted--robots with humanlike 'faces' and 'voices'
will attract our attention, and prompt animistic responses.
And the more humanlike the robot's use of language,
and/or its 'thinking' processes (e.g. the way it plays chess:
see below), the more this will be true. Indeed, we already
have empirical evidence, some anecdotal and some systematic, that this is so.
The strength of people's spontaneous, nigh-irrepressible,
impulse to engage with, and even to empathize with, today's humanoid robots is illustrated--for instance--by people's reactions to Cog, Kismet, and Leonardo (Breazeal and
Scassellati 2000, 2002). The MIT research team report that
visitors to the laboratory typically show not only curiosity,
but also something very like a genuinely human response
to their robots.
A particularly telling example has been reported by
Sherry Turkle--no naive observer, but someone with a
good understanding of AI. As she recalls the incident:
"Cog 'noticed' me soon after I entered its room. Its head
turned to follow me and I was embarrassed to note that this
made me happy. I found myself competing with another
visitor for its attention. At one point, I felt sure that Cog's
eyes had 'caught' my own. My visit left me shaken--not by
anything that Cog was able to accomplish but by my own
reaction to 'him'….Despite myself, and despite my continuing skepticism about this research project, I had behaved as though in the presence of another being" (Turkle
1995: 266). Her reaction is especially interesting given the
fact that Cog, unlike Kismet (which has floppy pink ears,
large blue eyes, and an amazing set of eyelashes), looks
nothing like an animal or human being.
IV: Human implications
If humanoid robots will elicit ToM-based reactions in human beings, that's not to say that the individuals concerned
will always (ever?) take those natural reactions at face
value. Like Turkle, they may be embarrassed by them, regarding them as utterly inappropriate. But our interest is
less in whether people actually believe that the robots are
genuine minds than in how their reactions to them affect
their thinking about humankind.
We must distinguish, here, between robots in particular
and AI in general. AI, with its close cousins computational
psychology and philosophy of mind, has already changed
the way that many literate people think about humanity.
For example, the reified Cartesion self has given way to the
self as a constructed narrative, which reflexively guides
one's motives, priorities, and actions to a significant,
though imperfect, degree (Minsky 1985; Dennett 1991: ch.
13). This notion, along with that of distributed cognition,
has even led the countercultural opponents of symbolic AI-postmodernists, feminists...--to welcome much recent AI
work, including situated robotics (e.g. Kember 2003). In
addition, computational accounts of freedom--more accurately, of the type of cognitive/motivational system that's
capable of making the sorts of decisions that we call free
choice--have demystified this concept in many people's
eyes (Dennett 1984; Boden 2006: 7.i.g).
As for belief in the uniqueness of humanity, this has seen
both advance and retreat. Advance, because AI research
has shown how hugely difficult (perhaps impossible) it is
to model the richness and subtlety of the average human
mind; retreat, because the sorts of things which humans,
alone among animals, can do can now be done at least to
some extent by artefacts. People are even (rashly, in my
view--Boden 2006: 14.x-xi) attributing consciousness to
some AI systems. More generally, the belief that human
psychology, consciousness included, is somehow generated
by a material system (the brain), as opposed to an immaterial soul, has been strengthened by AI as well as by neuroscience.
An advanced robotics will reinforce these alreadyfamiliar conceptual changes. But can anything more be
said? Will it add further changes that haven't yet happened?
If so, will those changes appear to bring us closer to robots,
or will they deepen the perceived division between humanity and AI? The answer lies in the issue of what philosophers and psychologists call embodiment.
Given the psychological mechanisms of ToM and gaze
mentioned above, it's easy to see why a 'look-alike' robot
may be able to excite people's interest, and to elicit empathy or fellow-feeling in them. Two gaze-locking eyes are
crucial, here. A one-eyed Cyclopean robot would be experienced not only as alien (as Gary Kasparov remarked
about Deep Blue's chess-playing), but as positively repul-
sive. Even a superficial coating of fur, or a humanlike gait
(with humanlike blunders), can help induce our sympathies. Consider Steve Grand's (2000) robot-gorilla Lucy,
for example: this wouldn't have attracted so much attention
from the media, or from highly articulate cultural critics
(e.g. Fox-Keller forthcoming), without its fur coat. And the
fact that the robot (unlike a VR character or avatar) is a
physical thing, moving around in the material world--and
encountering obstacles from time to time--much as we do
ourselves, strengthens the illusion.
However, embodiment is more than mere physicality
(materiality), even a physicality which outwardly resembles human bodies. To define it adequately, and to distinguish the many different senses in which the term is used,
would take many pages (see Clark 1997; Wheeler 2005).
Let's just say that it refers to a physical system-paradigmatically, an animal organism--that is situated in a
material world with which it interacts continuously, and
often more or less directly. (In my view, that "often" is
important, despite situated roboticists' repeated efforts to
deny the role of representations: Brooks 1991; Kirsh 1991.)
Indeed, many disciples of embodiment speak less of "interaction" here than of "dynamical coupling".
The notion of interaction suggests the possibility of the
system's deciding not to interact. Or, since oxygen-intake
(for instance) must go on without interruption, the idea is
that psychological interaction, or mental engagement, with
the environment need not be continuous. Quite apart from
sleep, the picture is that we may be lost in thought--with a
rich mental panoply going on internally, irrespective of
what's happening outside. (The ability of some people to
override the horrors of the concentration camps, or of solitary confinement in the Gulag, could be cited here.) In
theoretical psychology, talk of interaction may recall the
Cartesian "sandwich": sensory perception, motor action,
and purely mental processes in between. And much as a
picnicker can eat just one slice of bread, or only the turkeyfilling, so a psychologist can (on this view) admissibly
theorize about only perception, or motor action, or thought-without bearing the other two parts of the sandwich constantly in mind.
By contrast, to speak of coupling is to posit one dynam ical system (the organism) in close physical contact--and,
crucially, a relation of mutual determination--with another
(the environment). Indeed, the brain itself, or the visual
cortex, or a single neurone ... can be thought of as a dynamical system (Maturana and Varela 1980). By the same
token, plant and animal species can be thought of as systems within (closely coupled with) the earth as a whole
(Lovelock 1988). Life, on this view, is quintessentially
dynamic and environmentally grounded--and so is mind.
This approach leads to various questions that relate to the
interpretation of any future robotics. For instance, just what
is to count as motor action? I suggested, above, that a gazelocking robot, or one with humanoid limbs and gait, would
engage our attention. And so it would, for a while. But
what if we were convinced--as a stress on embodiment
suggests--that motor action (or behaviour) is no mere su-
perficial cue to the presence of mind, or intelligence, but an
ineliminable criterion of it? And what if we were also convinced that it must involve a close and continuous dynamical coupling with the physical environment? In that case,
it's not clear that even situated robots, with the ability to
react from time to time to environmental events, would be
counted as showing "lifelike" behaviour--irrespective of
whether their gait superficially resembled that of real cockroaches (Beer 1995) or real humans. Their initial attractiveness would very likely soon fade, as people realized the
difference between their mode of being and ours.
That's just one example of the fact that the differences
between robots and humans will be given prominence insofar as people attempt--as they doubtless will--to maintain a
distinction between the two. And a key concept in this differentiation is likely to be the concept of life.
It's often said that mind requires life. And certainly, all
the minds we know of are in living things. (Though not all
living things have minds: think of oak-trees.) Since robots
are not alive (so this argument goes) they can't have genuine intelligence, desires, or emotions ... so they can't pose a
fundamental challenge to our idea of humanity, or to the
unique place of Homo sapiens in the animal kingdom.
All very well--but there are two problems here. First, and
despite the hopes of A-Life researchers (Langton 1996;
Bedau 1996), there is still no universally accepted definition of life. Second, it's not clear that mind necessarily requires life. This "necessity" is usually taken for granted,
very rarely explicitly argued (Boden 2006: 16.x). So for
those with philosophical leanings, the brick wall between
robots and humankind may appear rather more flimsy than
it does to most people.
However, if we're concerned with the likely effect of i nteractive robotics on people in general, those relatively
arcane points can be ignored. Whatever life is, robots don't
have it.
(I've argued that this is because robots, and A-Life virtual
systems too, don't metabolize in the required sense: Boden
1999. Mere energy-usage, or even individually budgeted
'packets' of energy, isn't enough. The energy must be used
in the self-construction and bodily maintenance of the system, as well as in its functioning--which necessarily implies a complex interlocking set of metabolic cycles. These
need not, perhaps, be carbon-based. But the chemical passivity of robots, and their manufactured provenance, don't
fit metabolism as so defined.)
V: Conclusion
Advanced robotics, and especially interactive robotic
'companions', will affect how we think about human beings
in various ways. Some of these will reinforce the changes
to which AI in general has already led (a few were listed at
the outset of Section IV). One example, mentioned above,
is an increased respect for the richness and subtlety of human minds, because (or so I've argued in Section II) ro-
botics/AI won't be able to match the variety and power of
thought that we see in our neighbours and ourselves.
What robotics adds to 'screen-based' AI is physicality.
Certain types of physicality (e.g. two eyes, with varying
gaze) will unavoidably prompt ToM-based animistic responses. However, if the issue of embodiment is taken seriously then only robots of a very special kind (dynamically coupled with environment) would be philosophically
plausible as bearers of psychological predicates. Moreover,
even those would remain implausible for people who regard life as necessary for mind. For robots aren't living
things.
It's not obvious that mind necessarily requires life. (As
remarked above, this common assumption is very rarely
explicitly defended.) But if it does, our 'natural' animistic
responses to robots are ultimately as inappropriate as are
our empathetic responses to teddy bears.
An emphasis on life as the basis for mind could lead us to
take our biological nature more seriously. At present, in
industrial cultures, the fact that we're biological organisms
is largely forgotten--until something goes wrong, at which
point we head for the hospital. Admittedly, our biological
aspect has been highlighted by recent worries about foodadditives, environmental pollution, and global warming.
But it's commonly assumed that technology will trump
ecology. If advances in robotics lead us (by the sort of
'distancing' argument sketched above) to have greater respect for our human nature as living organisms, perhaps
that's all to the good.
Acknowledgments
This paper was supported by British Academy grant no.
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